1. Field of Invention
This invention is in the general field of solid-body electric guitars and, more particularly, is an apparatus and method for causing a tremolo effect on sound produced by a solid-body electric guitar in response to positioning a tremolo arm that is mounted on the body of the guitar.
2. Background of the Invention
A solid-body electric guitar is an almost purely electronic instrument. One or more pickups are connected to each of the strings of the solid-body guitar. In response to vibration of the strings, the pickups generate electrical signals that are combined and amplified to provide an audio signal that drives one or more loudspeakers.
Very little energy of vibration is transferred from the strings. Therefore, string vibration is sustained longer than corresponding vibration in other string instruments. As a result, a solid-body guitar sound caused by plucking a string is sustained longer than sound provided by the other string instruments.
A guitarist may choose to cause a tremolo effect whereby the pitch of the solid-body guitar sound is changed during the time that it is sustained. In one type of solid-body guitar, the tremolo effect is attained in response to the guitarist operating a foot pedal that is coupled to a potentiometer. A signal from the potentiometer causes a modification of the audio signal that results in the tremolo effect.
In another type of solid-body guitar, the tremolo effect is attained in response to the guitarist manually changing the position of a tremolo arm that is connected to a bridge over which the strings pass. Changing the position of the tremolo arm causes a corresponding change in the position of the bridge. The change in the position of the bridge changes the tension of the strings, thereby changing the tuning of the strings. Typically, the tremolo arm is connected to springs that provide the guitarist with tactile feedback of the position of the tremolo arm.
Most guitarists prefer to manually change the position of the tremolo arm rather than operate the foot pedal. In particular, foot pedals are difficult to control, as a user has more control over his arm/hand than his foot. Further, during concerts and the like, the presence of a foot pedal may be dangerous when left on a stage where a band member may trip on it. Alternatively, even when left on a stage, because the guitarist is often moving around, the foot pedal is often not in the desired location for use.
On the other hand, while a guitar-mounted mechanical tremolo is preferred, these current tremolos have the disadvantage of changing the tension of the strings to attain the tremolo effect, rapidly causes an undesired detuning of the strings. This can result in detuning of a guitar during a concert or the like, forcing the guitarist to change guitars or retune in the middle of the concert.